Here’s Why Your Roulette Table Has a Compass

Casinos are always on the lookout for cheaters.

Everyone knows about the “eye in the sky,” the sophisticated surveillance systems watching every customer and employee in a casino.

But sometimes casinos rely on old-school technology, too.

That’s why you’ll often see compasses built into roulette tables in Las Vegas casinos.

If you think compasses are proliferating on roulette tables, you have a point.

See, scam artists have occasionally used magnets and altered balls to cheat casinos at roulette.

It’s worth noting the name of our band in high school was Altered Balls, but that’s for another time.

Compasses detect the Earth’s natural magnetic fields, with the needle always pointing to magnetic north.

The theory is anyone trying to use magnets to alter the outcome of a roulette spin (presumably they’d swap out a ball for one with a metallic core) would be detected because the compass needle would act erratically or point in a direction other than north, thus foiling the cheater.

Compasses are a presumably a visual deterrent to cheaters, but one longtime casino manager we talk to said, “They’re dumb and mostly for show.”

Longtime casino managers don’t mince words.

We couldn’t find much online about the use of compasses to detect cheating in casinos. Presumably, casinos don’t want such information out there, as crooks are always looking for vulnerabilities in security systems.

Casino security is a never-ending game of cat and mouse with boneheads looking to make a quick buck.

A compass that points both north and south is very useful if you’re trying to find the Neon Museum (north) or Pinball Museum (south).

It’s worth noting casinos have long been accused of using magnets to cheat players, but that’s nonsense. Why is it nonsense? Because the house edge at roulette is steep. Casinos don’t need to cheat.

Poor player odds at roulette have gotten even worse with the use of tables with not just a zero and double zero, but triple zero.

Double zero tables have a house advantage of 5.26%. A table with three zeros has a house edge up to 7.69%.

Read more about triple zero roulette.

Triple Zero Sands Roulette
Las Vegas Sands has done a lot of great things. Being the first to do this wasn’t one of them.

The use of compasses to thwart roulette cheats is just one of many ways casinos protect the integrity of their games.

Some blackjack tables have red card discard trays. Casinos use red so dealers and surveillance can detect a cheater marking cards with ink.

Blackjack discard tray
Now you know.

Craps dice have always been a source of frustration for casino security. Dice tampering is an ongoing threat, so casinos use a variety of techniques to ensure rolls are random. (Again, the house edge is built into every roll, so casinos are more concerned games are fair so customers keep playing.)

Every detail is considered when producing and monitoring dice. For example, dice makers don’t paint pips, or spots, on dice. Holes are drilled, then filled with a special paint that’s the exact weight and density as the die. That way, dice remain perfectly balanced.

Dice pips drilling filling
Try and use the term “backfilling” at parties. It will make you sexier.

Don’t get us started about dice pips.

Read more about casino dice security measures.

So, if you’re playing roulette and see a compass built into the table, it’s not because casinos think you’re lost (although, that’s not uncommon in some Strip casinos, they’re huge).

Compasses are a simple, inexpensive and clever way to fend off chicanery, or at least to make miscreants think twice before mucking with a casino’s balls.